Acıbadem Üniversitesi Açık Erişim Sistemi
Not a member yet
2603 research outputs found
Sort by
Generation of Bone Tissue Using Adipose Tissue-derived Stem Cells
No full textObjective: Bone grafts and even bone substitutes do not meet all of the requirements of bony reconstructions. The aim of this study was to generate bone tissue from autologous adipose tissue-derived mesenchymal stem cells (ATDMSCs) and decellularised bone allografts. Methods: A 1.5 cm bone defect developed in the middle third of the rabbit's ulna. Reconstructions were carried out using miniplate and screws and interpositional autogenous bone grafts according to the designs of the groups: (1) No touch, (2) cryopreserved, (3) decellularised and (4) ATDMSCs-implanted decellularised bones. Before implantation, ATDMSCs in the last group were labelled with Q-dot and identified microscopically. Results: Graft recovery and irregular callus formation were observed in the first, second and forth groups. In the first group, the organisation of Haversian systems, the structure of the lacunae and the presence of canaliculi ossiums were observedin the second group, approximately 40\% of the Haversian canals contained blood vessels, and canaliculi ossiums in the form of thin filaments were found in 90\% of the microscopically examined areasin the third group, most Haversian canals were empty, most osteocyte canals were devoid of cells, and canaliculi ossiums were absentin the fourth group, some of the Haversian canals contained blood vessels, and there were partly lacunae containing cells due to decellularisation, whereas in approximately 50\% of the examined microscope areas, the presence of canaliculi ossiums with evidence of mesenchymal stem cells differentiated into osteocytes was demonstrated by Q-dot traced cells. Conclusion: In this study, the establishment of a proper niche environment for adipose-derived mesenchymal cells promotes their development into osteogenic cells.3JUL294-300
External Validation of the DynPG for Kidney Transplant Recipients
No full textBackground. In kidney transplantation, dynamic prediction of patient and kidney graft survival (DynPG) may help to promote therapeutic alliance by delivering personalized evidence-based information about long-term graft survival for kidney transplant recipients. The objective of the current study is to externally validate the DynPG. Methods. Based on 6 baseline variables, the DynPG can be updated with any new serum creatinine measure available during the follow-up. From an external validation sample of 1637 kidney recipients with a functioning graft at 1-year posttransplantation from 2 European transplantation centers, we assessed the prognostic performance of the DynPG. Results. As one can expect from an external validation sample, differences in several recipient, donor, and transplantation characteristics compared with the learning sample were observed. Patients were mainly transplanted from deceased donors (91.6\% versus 84.8\%P < 0.01), were less immunized against HLA class I (18.4\% versus 32.7\%P < 0.01) and presented less comorbidities (62.2\% for hypertension versus 82.7\%, P < 0.0125.1\% for cardiovascular disease versus 33.9\%, P < 0.01). Despite these noteworthy differences, the area under the ROC curve varied from 0.70 (95\% confidence interval {[}CI], 0.64-0.76) to 0.76 (95\% CI, 0.64-0.88) for prediction times at 1 and 6 years posttransplantation respectively, and calibration plots revealed reasonably accurate predictions. Conclusions. We validated the prognostic capacities of the DynPG in terms of both discrimination and calibration. Our study showed the robustness of the DynPG for informing both the patient and the physician, and its transportability for a cohort presenting different features than the one used for the DynPG development.2FEB396-40310
Safe and persistent growth-promoting effects of vosoritide in children with achondroplasia: 2-year results from an open-label, phase 3 extension study
No full textPurpose Achondroplasia is caused by pathogenic variants in the fibroblast growth factor receptor 3 gene that lead to impaired endochondral ossification. Vosoritide, an analog of C-type natriuretic peptide, stimulates endochondral bone growth and is in development for the treatment of achondroplasia. This phase 3 extension study was conducted to document the efficacy and safety of continuous, daily vosoritide treatment in children with achondroplasia, and the two-year results are reported. Methods After completing at least six months of a baseline observational growth study, and 52 weeks in a double-blind, placebo-controlled study, participants were eligible to continue treatment in an open-label extension study, where all participants received vosoritide at a dose of 15.0 mu g/kg/day. Results In children randomized to vosoritide, annualized growth velocity increased from 4.26 cm/year at baseline to 5.39 cm/year at 52 weeks and 5.52 cm/year at week 104. In children who crossed over from placebo to vosoritide in the extension study, annualized growth velocity increased from 3.81 cm/year at week 52 to 5.43 cm/year at week 104. No new adverse effects of vosoritide were detected. Conclusion Vosoritide treatment has safe and persistent growth-promoting effects in children with achondroplasia treated daily for two years.12DEC2443-24472
Is it safe to perform elective gynaecologic surgery during the two peaks of COVID-19 pandemic?
No full textPurpose In December 2019, the COVID-19 pandemic started in China and spread around the World. Operations were postponed in most surgical clinics to reduce the risk of contamination and increase the number of beds available in hospitals. We investigate whether elective gynaecologic surgery is safe or not under safety measures. Methods A total of 765 patients were operated on electively between 15 March and 30 October 2020 at our inpatient gynaecology clinic. We took the SARS-CoV-2 Reverse Transcriptase (RT) Polymerase Chain Reaction (PCR) test of the nasopharyngeal swab before and after the surgery. Patients were questioned for COVID-19 symptoms by phone calls on the 7th, 15th, 30th and 60th days postoperatively. Results The average age of patients was 45.6 +/- 11(19-81). Sixty-two (8.1\%) operations were performed due to gynaecologic malignancies. Three patients (0.39\%) were detected as SARS-CoV-2 RT PCR positive within 7 days after surgery. The patients did not need ICU admission or any further treatments. Conclusion Our study offers a novel perspective on elective surgery during a pandemic. The risk assessment of patients should be meticulously done and substantiated on objective variables. According to our study, in a carefully selected patient population, operating under appropriate precautions, elective gynaecologic surgical procedures during the two peaks of the COVID-19 pandemic do not pose a risk to the patients.11NOV7
Persistent Ambient Air Pollution in Turkey: A 4-Year Analysis
No full textOBJECTIVE: Ambient air pollution is an important cause of morbidity and mortality for both individual and public health. The major contaminant that creates air pollution in Turkey is particulate matter. This study aims to demonstrate Turkey's air quality in terms of particulate matter in the last 4 years. MATERIAL AND METHODS: In this descriptive study, the public data of the National Air Quality Monitoring Network between the years 2016 and 2019 were analyzed for particulate matter (PM10). Stations with less than 75\% data throughout the year were excluded from the evaluation while calculating the annual average values. The averages of the years were compared statistically with each other. RESULTS: For 111 stations that made sufficient measurements for 4 years, the annual median value of particulate matter remained constant in 12 stations (10.8\%), increased in 26 stations (23.4\%), and decreased in 73 stations (65.7\%). The level of air pollution at 18 stations has been sustained for 4 years. It has been observed that there is no significant improvement in the criterion that the daily average PM10 level should not be higher than 50 mu g/m(3) for more than 35 days, and pollution is detected above the limit value permitted by the World Health Organization in all provinces and stations except a few provinces every year. Finally, during the 4-year observation, the number of stations that did not make sufficient measurements throughout the year has been found to increase over the years. CONCLUSION: Our data reveal that the air pollution attributable to particulate matter in Turkey between the years 2016 and 2019 did not regress prominently. On the contrary, air pollution has been found to gain permanency in certain provinces, and air quality monitoring has been inadequate due to insufficient measurement activities of some of the stations.6NOV482-4882
Surgical procedures for coronary arteries in pediatric cardiac surgery: Risk factors and outcomes
No full textBackground Limited data exist regarding the coronary revascularization procedures needed during the repair of several congenital and pediatric cardiac malformations. We aimed to determine risk factors for in-hospital mortality and long-term outcomes of various pediatric coronary revascularization procedures. Methods We retrospectively reviewed the records of 32 consecutive pediatric patients who underwent coronary revascularization procedures at our institution between May 1995 and June 2020. In-hospital mortality, risk factors, surgical indications, revascularization patency, and mid- and long-term follow-up data were investigated. Patients were categorized into the coronary artery bypass grafting (n = 11) and other coronary artery procedure (n = 21) groups. Results The median age and weight of patients at the time of surgery were 9 months and 4.8 kg, respectively. There were five in-hospital deaths (5/32, 15.6\%). The mortality rates were 27.2\% (3/11) in the coronary artery bypass grafting group and 9.5\% (2/21) in the other coronary artery procedure group (p = .20695\% confidence interval: 0.496-25.563). The mortality rates for planned and rescue procedures were 8.3\% (2/24) and 37.5\% (3/8) (p = .06), respectively. The median follow-up time was 12.5 years. Control imaging studies for coronary patency were performed in 70.3\% (19/27) of surviving patients. The overall coronary patency rate was 94.7\% (18/19). Conclusions Pediatric coronary revascularization procedures with elective-planned indications can be performed with good outcomes. Young age and rescue and emergency procedures may carry an increased risk of in-hospital mortality, although not found to be statistically significant. Surviving patients require lifelong follow-up regarding the patency of reperfused coronary arteries.7JUL2289-22993
THE EFFECT OF PATERNALIST LEADERSHIP ON ORGANIZATIONAL CITIZENSHIP BEHAVIOR
No full textThe aim of this study is to examine the impact of paternalist leadership behaviors on organizational citizenship behavior. The sample of the study consists of 535 healthcare professionals working in a private hospital in Istanbul. Correlation Analysis and Simple Linear Regression Analysis were used to examine the relationship between the measured variables. As a result of the research, it was found that paternalist leadership has a positive and moderate effect on organizational citizenship behavior (r = 0.427, p <0.01) and 18.3\% of the changes in organizational citizenship behavior are explained by paternalist leadership. Our study shows that paternalistic leadership has a significant impact on the organizational citizenship behavior of health workers. By exhibiting paternalistic leadership behavior, health administrators can enable health workers to display more organizational citizenship behavior.2JUL893-906
Investigation of neuro-inflammatory parameters in a cuprizone induced mouse model of multiple sclerosis
No full textCuprizone, copper chelator, treatment of mouse is a toxic model of multiple sclerosis (MS) in which oligodendrocyte death, demyelination and remyelination can be observed. Understanding T and B cell subset as well as their cytokines involved in MS pathogenesis still requires further scrutiny to better understand immune component of MS. The study presented here, aimed to evaluate relevant cytokines, lymphocytes, and gene expressions profiles during demyelination and remyelination in the cuprizone mouse model of MS. Eighty male C57BL/6J mice fed with 0.2\% cuprizone for eight weeks. Cuprizone has been removed from the diet in the following eight weeks. Cuprizone treated and control mice sacrificed biweekly, and corpus callosum of the brain was investigated by staining. Lymphocyte cells of mice analyzed by flow cytometry with CD3e, CD11b, CD19, CD80, CD86, CD4, CD25 and FOXP3 antibodies. IFNgamma, IL-1alpha, IL-2, IL-5, IL-6, IL-10, IL-17, TNF-alpha cytokines were analyzed in plasma samples. Neuregulin 1 (Nrg1), ciliary neurotrophic factor (Cntf) and C-X-C chemokine receptor type 4 (Cxcr4) gene expressions in corpus callosum sections of the mice brain were quantified. Histochemistry analysis showed that demyelination began at the fourth week of cuprizone administration and total demyelination occurred at the twelfth week in chronic model. Remyelination occurred at the fourth week of following withdrawal of cuprizone from diet. The level of mature and activated T cells, regulatory T cells, T helper cells and mature B cells increased during demyelination and decreased when cuprizone removed from diet. Further, both type 1 and type 2 cytokines together with the proinflammatory cytokines increased. The level of oligodendrocyte maturation and survival genes showed differential gene expression in parallel to that of demyelination and remyelination. In conclusion, for the first-time, involvement of both cellular immune response and antibody response as well as oligodendrocyte maturation and survival factors having role in demyelination and remyelination of cuprizone mouse model of MS have been shown.5644+4